This invention relates to an article of footwear, such as a shoe, so adapted as to permit ventilation of the interior of the footwear.
Various footwear configurations designed to promote ventilation of the interior of the article of footwear are known in the art. A typical article of such footwear, such as a shoe, includes an outer sole and inner sole delimiting a vacant space between them, hollow pump members made of a flexible material disposed in the vacant space at the toe end of the shoe, and supporting bodies also disposed in the vacant space for maintaining the shape thereof. Each pump member has an upper surface provided with air intake holes, and a rear portion provided with air discharge holes. The inner sole is provided with ventilating holes for communicating the air within the vacant space with the air inside of the shoe proper. When the weight of the wearer is applied to the shoe as the wearer walks, the inner sole is deformed downwardly to compress the pump members while the wearer's foot blocks the air intake holes formed in the pump members. Consequently, the air enclosed within the pump members is expelled into the rear portion of the shoe from the air discharge holes. The expelled air exits from the shoe from the area surrounding the wearer's angle by passing through the ventilating holes formed in the inner sole. As the wearer continues to walk and the shoe is lifted from the ground, the wearer's weight is removed from the shoe so that the pump members relax back to their original shape owing to their restorability. This causes the air in the vacant space between the inner and outer soles to be drawn in through the air intake holes, as well as the air in the shoe interior, which passes through the ventilating holes formed in the inner sole. Thus, the arrangement is such that the air within the shoe is ventilated by means of a circulatory air flow.
Although the shoe of the aforementioned construction is ventilated in the desired fashion, the shoe does have certain disadvantages. Specifically, the fact that several individual pump members and supporting members are disposed in the vacant space between the inner and outer soles results in a shoe which is complicated in construction, laborious to manufacture and, hence, high in cost. Since the pump members are required to have structural strength, moreover, it is necessary to use materials which are of considerable weight. This results in a heavy shoe which is uncomfortable to wear.